The Changing Trend of Paediatric Emergency Department Visits in Malaysia Following the COVID-19 Pandemic

Background The coronavirus disease 2019 (COVID-19) pandemic has impacted the emergency department (ED) due to the surge in medical demand and changes in the characteristics of paediatric visits. Additionally, the trend for paediatric ED visits has decreased globally, secondary to implementing lockdowns to stop the spread of COVID-19. We aim to study the trend and characteristics of paediatric ED visits following Malaysia's primary timeline of the COVID-19 pandemic. Methods and materials A five-year time series observational study of paediatric ED patients from two tertiary hospitals in Malaysia was conducted from March 17, 2017 (week 11 2017) to March 17, 2022 (week 12 2022). Aggregated weekly data were analysed using R statistical software version 4.2.2 (R Foundation for Statistical Computing, Vienna, Austria) against significant events during the COVID-19 pandemic to detect influential changepoints in the trend. The data collected were the number of ED visits, triage severity, visit outcomes and ED discharge diagnosis. Results Overall, 175,737 paediatric ED visits were recorded with a median age of three years and predominantly males (56.8%). A 57.57% (p<0.00) reduction in the average weekly ED visits was observed during the Movement Control Order (MCO) period. Despite the increase in the proportion of urgent (odds ratio (OR): 1.23, p<0.00) and emergent or life-threatening (OR: 1.79, p<0.00) cases, the proportion of admissions decreased. Whilst the changepoints during the MCO indicated a rise in respiratory, fever or other infectious diseases, or gastrointestinal conditions, diagnosis of complications originating from the perinatal period declined from July 19, 2021 (week 29 2021). Conclusion The incongruent change in disease severity and hospital admission reflects the potential effects of the healthcare system reform and socioeconomic impact as the pandemic evolves. Future studies on parental motivation to seek emergency medical attention may provide insight into the timing and choice of healthcare service utilisation.

Hybrid fuzzy inference rules of descent method and wavelet function for volatility forecasting

This research employs the gradient descent learning (FIR.DM) approach as a learning process in a nonlinear spectral model of maximum overlapping discrete wavelet transform (MODWT) to improve volatility prediction of daily stock market prices using Saudi Arabia's stock exchange (Tadawul) data. The MODWT comprises five mathematical functions and fuzzy inference rules. The inputs are the oil price (Loil) and repo rate (Repo) according to multiple regression correlation, and the Engle and Granger Causality test Engle RF, (1987). The logarithm of the stock market price (LSCS) in Tadawul reflects the output variable. The correlation matrix reveals that there is no collinearity between the input variables, and the causality test demonstrates that the input variables significantly influence the outcome variable. According to the multiple regression, there is a substantial negative influence between Loil and LSCS but a significant positive effect between Repo and output. For the 80% dataset under ME (0.000005), MAE (0.003214), and MAPE (0.064497), the MODWT-LA8 (ARIMA(1,1,0) with drift) for the LSCS variable performs better than other WT functions. In the novel hybrid model MODWT-FIR.DM, each function's approximation coefficient (LSCS) is applied with input variables (Loil and Repo). We evaluate the performance of the proposed model (MODWT-LA8-FIR.DM) using different statistical measures (ME, RMSE, MAE, MPE) and compare it to two established models: the original FIR.DM and other MODWT-FIR.DM functions for forecasting 20% of datasets. The outcomes show that the MODWT-LA8-FIR.DM performs better than the traditional models based on lower ME (3.167586), RMSE (3.167638), MAE (3.167586), and MPE (80.860849). The proposed hybrid model may be a potential stock market forecasting model.

A Comparative Analysis of Semiparametric Tests for Fractional Cointegration in Panel Data Models

Several authors have studied fractional cointegration in time series data, but little or no consideration has been extended to panel data settings. Therefore, in this paper, we compare the finite sample behaviour of existing fractional cointegration time-series test procedures in panel data settings. This comparison is performed to determine the best tests that can be adapted to fractional cointegration in panel data settings. Specifically, simulation studies and real-life data analysis were performed to study the changes in the empirical type I error rate and power of six semiparametric fractional cointegration tests in panel settings. The various results revealed the limitations of the tests in the nonstationary and low or high correlation of the residual errors conditions. Also, two of the test procedures were recommended for testing the null hypothesis of no fractional cointegration in both time series and panel data settings.

Performance of a Novel Hybrid Model Through Simulation and Historical Financial Data

It is thoroughly acknowledged that the historical financial time series is not linear, exhibits structural changes, and is volatile. It has been noticed in the current literature that because of the existence of structural breaks in the historical time series, the GARCH family models provide misleading results and poor forecasts. Thus, it is unavoidable to incorporate models with nonlinearity in the conditional mean and conditional variance to capture volatility dynamics more precisely than the existing models. Therefore, inspiring in this matter, this study proposes a novel hybrid model of exponential autoregressive (ExpAR) with a Markov-switching GARCH (MSGARCH) model. This study also examines volatility dynamics and performances through simulation and real-world financial data. Moreover, this study investigates downside risk management performances using 5% VaR (Value-at-Risk) back-testing. The empirical findings showed that the proposed model outperforms the benchmark model for both simulation and real-world time series data. The VaR results also showed that the proposed model captures downside risk more meticulously than the benchmark model.

An EPQ Model for Delayed Deteriorating Items with Two-Phase Production Period, Exponential Demand Rate and Linear Holding Cost

The economic production quantity (EPQ) model for delayed deteriorating items considering two-phase production periods, exponential demand rate and linearly increasing function of time holding cost is proposed to solve a production problem similar to the one caused by the Covid-19 pandemic. Without shortages, the necessary and sufficient conditions for optimality of this model are characterized through a theorem and lemmas while a solution methodology based on differential calculus is adopted. This paper determines the best replenishment cycle length corresponding to the optimal total variable cost and production quantity of imperfect production industry. To illustrate this model, a numerical experiment is conducted. The results demonstrate that a higher carrying charge decreases the production quantity and a longer demanding period decreases the total variable cost of an industry with a distracted production period. Finally, managerial insights are discussed using sensitivity analysis and future research directions are exposed.

OR6. Ankle-brachial index is associated with carotid intima-media thickness in type 2 diabetes mellitus patients

Background and Aims

Atherosclerosis and its complications occur more rapidly in diabetes mellitus. Early detection remains a challenge. Carotid intima-media thickness (CIMT) has been used widely and validated marker for detecting subclinical atherosclerosis. The limitation of this examination is operator dependence. Meanwhile, ankle-brachial index (ABI) examination is easier and widely available. This study is aimed to evaluate correlation ABI and CIMT in type 2 diabetes mellitus patients.

Method and Results

We conducted cross-sectional study in vascular outpatient clinic of Dr. Sardjito Hospital. Fifty-one patients were taken by purposive sampling. An interview, hematological parameters, lipid profiles, anthropometric, ABI, and CIMT measurement were performed. ABI was measured by doppler ultrasound, meanwhile an ultrasound examination of both common carotid artery was done to obtain the CIMT. Subjects were 49.02% females and 50.98% males, with mean age 59.22 ± 8.8 years old. The percentages of hypertension, dyslipidemia, smoking, obesity, metabolic syndrome, coronary artery disease, congestive heart failure, and chronic kidney disease were 60.8%, 51%, 27.5%, 52.9%, 72.5%, 31.4%, 9.8%, and 9.8%, respectively. Bivariate analysis showed mean ABI in the presence of mean CIMT ≥1mm and/or carotid plaque were lower (1.05±0.17 vs 1.16±0.08, p = 0.016). Proportions mean and maximum CIMT ≥1mm were 15.7% and 33.3%, respectively. Pearson’s correlation showed ABI was negatively correlated with mean CIMT and maximum CIMT (r=-0.334, p = 0.017; r=-0.299, p = 0.033).

Conclusion

Ankle-brachial index is negatively correlated with carotid intima-media thickness. Therefore, in limited facility, ABI examination might be performed for predicting subclinical atherosclerosis.

The determinants of electricity consumption for ASEAN countries

The present study investigates the causal relationship between ASEAN seven member countries electricity consumption (EC) and some determinants such as gross domestic product (GDP), exports (EXP) and carbon dioxide emission (CO2) using vector autoregressive (VAR) framework via vector error correction (VEC) model for the period from 1980-2015. The findings show that the effect of the chosen determinants is different among the seven countries. Within the sample period, by utilizing Granger causality test, out of the seven countries, only four revealed either unidirectional or bidirectional causality running from EC to the three determinants, GDP, EXP and CO2. Whereas, thru forecast error variance decomposition (FEVD), forecasting beyond the sample period uncovered a shock to EC will also spread to GDP, EXP and CO2. The present study suggests that ASEAN should take note in designing their electricity policy, since electricity affect and be affected by other factors. In addition, ASEAN also should find solutions on how to control CO2 emission through EC.

Epidemiological survey of dermatophytosis in Damascus, Syria, from 2008 to 2016

Background and Purpose:

It is important to follow annually the probable changes in distribution pattern of dermatophytosis and its etiological agents in different communities. In this study, we determined the prevalence of dermatophytosis and its causative agents in Damascus, Syria, between 2008 and 2016.

Materials and Methods:

A total of 4080 outpatients who visited the dermatological clinics in Damascus, were evaluated. The specimens were collected from clinically suspected tinea. The patients were referred to our laboratory for direct examination by 30 %KOH. Some of the specimens were cultured on Sabouraud Dextrose Agar for fungal identification.

Results:

Out of the 4080 cases, 1138 cases were positive in direct examination(%27.89) , including Tinea pedis (%46.98), followed by tinea capitis(%39.79) , tinea corporis (%25.38), toenail onychomycosi (%20.33), tinea manuum (%16.06), and fingernail onychomycosis .(%15.22) Tinea pedis and toenail onychomycosis were more common in summer %41.19) and %25.78 respectively .(Trichophytic rubrum was the most prevalent fungal pathogen, especially in toenail onychomycosis.

Conclusion:

Dermatophytosis is highly prevalent in Syria. This study provides valuable data for differential diagnosis of dermatophytosis.

Detecting regime shifts in Malaysian exchange rates

Many financial and economic time series undergo episodes where the behaviour of the series seems to change quite dramatically. Such phenomena’s are referred to as regime shifts and cannot be modelled by a single equation linear model. Therefore to overcome this problem a nonlinear time series model is typically designed to accommodate this nonlinear feature in the data. In this paper, we use a univariate 2-regime Markov switching autoregressive model (MSAR) to capture regime shifts behaviour in both the mean and the variance in Malaysia ringgit exchange rates against four other countries namely the British pound sterling, the Australian dollar, the Singapore dollar and the Japanese yen between 1990 and 2005. The MS-AR model is found to successfully capture the timing of regime shifts in the four series and this regime shifts occurred because of financial crises such as the European financial crisis in 1992 and the Asian financial crisis in 1997. Furthermore, the significant result of the likelihood ratio test (LR test) justified the used of nonlinear MS-AR model rather than linear AR model.

Application of empirical mode decomposition with local linear quantile regression in financial time series forecasting

This paper mainly forecasts the daily closing price of stock markets. We propose a two-stage technique that combines the empirical mode decomposition (EMD) with nonparametric methods of local linear quantile (LLQ). We use the proposed technique, EMD-LLQ, to forecast two stock index time series. Detailed experiments are implemented for the proposed method, in which EMD-LPQ, EMD, and Holt-Winter methods are compared. The proposed EMD-LPQ model is determined to be superior to the EMD and Holt-Winter methods in predicting the stock closing prices.

Sex pheromones inCulicoides nubeculosus (diptera, ceratopogonidae): Possible sites of production and emission

This study was performed on virgin females ofCulicoides nubeculosus to determine sites of production and emission of sex pheromone. The ventral abdominal surface is the site of emission of the pheromone. Morphologically there is evidence of the presence of abdominal atrichial areas. The abdominal areas, eight per segment (four ventral and four dorsal), are covered by a cuticle devoid of micro- and macrotrichiae. The dorsal and ventral areas differ considerably in their structure. The dorsal atrichial areas have an unperforated cuticle covering a normal epidermis, whereas the ventral atrichial areas have a cuticle perforated by numerous tubular structures, with a loosely organized procuticle and no underlying epidermal cells. A pair of voluminous cells with the classical ultrastructural characteristics of enocytes is invariably located in the vicinity of the ventral atrichial areas. These cells undergo ultrastructural modifications tending towards involution according to the age of the insects, being correlated with the decrease in pheromone emission by older females. The hypothesis is put forward that enocytes are involved in pheromone production.

Are sperm motion parameters influenced by varicocele ligation?

OBJECTIVE

To document objectively, improvements in sperm motion parameters in subfertile men after varicocele ligation with the use of computer-aided sperm analysis.

DESIGN

Retrospective chart review.

SETTING

An academic clinical environment.

PATIENT(S)

Thirty-four men with varicocele as the primary cause of infertility who underwent a physical examination, hormonal profile, and Doppler ultrasound evaluation.

INTERVENTION(S)

Computer-aided sperm analysis was performed before and after either subinguinal or laparoscopic varicocele ligation.

MAIN OUTCOME MEASURE(S)

Patients were followed up for 3-18 months after operation, and average computer-aided sperm analysis values were obtained before and after operation. Computer-aided sperm analysis values were analyzed by paired Student's t-test, with special reference to motility and sperm motion parameters.

RESULT(S)

After varicocele ligation, patients demonstrated increases in mean sperm density and in the overall distribution of sperm with rapid velocity, although the increases were not statistically significant. Mean measures of straightness, linearity, and track speed also were increased after operation, but only progressive sperm velocity was increased to a statistically significant level.

CONCLUSION(S)

Because progressive velocity has been a primary computer-aided sperm analysis parameter predictive of male fertility and the success of assisted reproductive techniques, we conclude that varicocele ligation results in improvements in semen parameters, especially the key parameter of progressive sperm velocity.

[The sexual activity of Culicoides nubeculosus (Mg.) (Diptera, Ceratopogonidae) (author's transl)]

The sexual activity of C. nubeculosus has been studied in relation to the age of males and females. The criteria chosen were stoutness of spermatheca and frequency of mating, respectively. A unit N. M. H. (number of matings/male/hour) has been determined. Sexual activity reaches its maximum on 2nd day of imaginal life and is then slowly decreasing. This maximum activity on 2nd day rapidly decreases in the hours following blood meal, down to a rate which then remains nearly constant.

[Effect of blood meal on the secretion of pheromone by females of C. nubeculosus (Diptera, Ceratopogonidae) (author's transl)]

In a previous study, we showed that virgin females of C. nubeculosus secrete a sex pheromone which attracts males of the same species and stimulates mating. We consider that a number of physiological factors may be capable of modifying this secretion. In this study, we have investigated the effect of a blood meal on secretion of the pheromone by virgin females. No change in secretion of the pheromone was observed during the blood meal, but a decrease was evident during the next few hours. This decrease continues up to 24 hours after the blood meal, by which time oogenesis has started. At 48 hours after the blood meal, when the eggs are mature, secretion of the pheromone increases. An even more pronounced increase is observed during the period of oviposition, occurring 3 to 4 days after the blood meal. Secretion of the pheromone subsequently diminishes.